It may have taken 4 hours, but I've open-sourced the Coaxial8or r3.1 heatblock so that I could participate in PCBWay's 7th Design Contest. 

R3.1 is essentially R3 with all the post-print alterations, but since I haven't reprinted, it's not the 4th revision. 

To get things ready to go IPO, I just did a few small tweaks today, such as 

• finding a better texture
• filleting the grub shield walls
• changing the leak paths to 
  • decrease the chance of leaks near the heater cartridge
  • increase the chance that material can be pulled out of the channels when the hotend is heated to around 100C (for PETG)
  • increase the speed at which a leak could be detected

I also tried my hand at the "configuration" feature that Fusion has had for a few months now:

Some of the limitations I found was that you can't edit in place, nor do things like change checkboxes (Eg. "Keep Tools" in a combine feature). But now, I can quickly toggle visibility of certain components:

I've also exported the .step of the hotend holder, partially because the odds that I need to continue revising it are not insignificant. Additionally, it's tangled in the rest of the "Coaxial Hotend" file and trying to "Save a copy" gave me an exploded file:

I've also rendered the latest heatblock and holder:

I read the Open-Source Hardware FAQ and confirmed my choice to use the CERN hardware license. I'm not sure if it matters much compared to Creative Commons in the grand scheme of things.